Safety device for presses and the like



' July W. T. MINETT- swam DEVICE FOR PRESSES AND THE LIKE Filed Feb. 20, 1939 Patented July 1, 1941 FFIQE Wilfrid 'ihomas ltiinett, Leicester, England, as-

signor to United Shoe Machinery Corporation,

Eorough of Flemington, N. .l., a corporation of New ersey Application February 20 in Great Brita Claims,

This invention relates to improvements in safety devices for presses. and the like and is herein illustrated, by way of example but not of limitation, as embodied in a machine for compressing leather heels.

Machines of the type above referred to are customarily set in operation by a treadle actuated by the foot of the operator, the article to be operated on being fed to the machine by hand, and there is ever present danger that the operator may accidentally start the machine before his hands are out of the danger Zone between the compressing members. The operator thus runs the risk of serious injury or permanent disability.

It is an object of the present invention to safeguard the operator against such danger by making it necessary for him to withdraw his hand from the danger Zone before he can start the machine. In the illustrated embodiment of the invention this is accomplished by requiring the use of the oper-ators hand as well as his foot in setting the machine into operation.

It is a further object of the invention to provide a mechanism such that after the machine has been stopped by releasing the treadle, the operator will be required to use his hand again before the machine can be restarted, thus removing any temptation to fasten and leave the hand-operated releasing mechanism in releasing position.

Accordingly, the invention comprises a starting treadle, means for locking the starting treadle in inoperative position, hand-operated means for releasing the locking mechanism and means for holding the releasing means out of cooperative relation with the locking mechanism from the time the releasing means is operated until it is returned to its initial position.

The invention will now be described in detail with reference to the accompanying drawing, in which- Fig. 1 shows an outline of a heel-compressing machine with the invention attached thereto; and

Fig. 2 is a view on a larger scale of the looking mechanism and parts cooperating therewith, portions being broken away to show the interior construction.

The invention, as illustrated, is embodied in a heel compressing machine of the type disclosed in Letters Patent of the United States No. 776,823, granted December 6, 1904, on the application of Charles L. Allen.

As shown in Fig. 1, a handle it is pivoted in a 1939, Serial No. 257,431 in May 12, 1938 projection it on the frame it of the heel compressing machine and is rigid with a, lever l2 connected to a rod E8 in such a manner that operation of the handle it depresses the rod 18. A spring 2%, connecting the projection Ni and the rod 58, holds the rod in raised position and tends to draw it toward the center line of the machine.

Referring now to Fig. 2, the rod it passes through a slot 24 in the upper surface of a box 22, containing a locking andreleasing mechanism. Aiplate 26 slidably secured to the top of the box 22 by set screws 28 permits lateral motion of the rod 18 but keeps the slot t l closed, thus preventing dirt and refuse from entering the box 22. y

A treadle (it, mounted at the base of the machine on a shaft 32 which operates the starting mechanism, has two pedal surfaces at and 35, and a curved arm 38 extending upwardly from its upper edge. A stud 50 attached to the inner side of the arm 38 projects through a curved slot 42 in a cover 4 of the box 22. The slot 52 is shaped to correspond Wtih the arc traced by the stud 48 as the latter moves downwardly when the treadle 30 is depressed. A catch 36 attached toa weighted lever 713 is so arranged that when in normal or looking position, it engages the stud t0 and prevents depression of the Itreadle 3B. The weighted lever 43 in normal position rests against a stop 59 projecting from the side of the box 22.

A plate 52 is attached to the other extremity 53 of the lever A8. This plate engages a shoulder 54 on the rod I8. The lower end 56 of the rod I8 is located just above an abutment 58 adjustably attached by a screw 60 to one end of a second weighted lever or dog 62. A stop 64 is located immediately beneath the abutment 58.

To set the machine in motion the operator moves the handle It, depressing the rod l8. Depression of the rod I8 causes the shoulder 54 to engage the plate 52 on the end of the lever 48. Continued pressure on the rod moves the end 53 of the lever 43 downwardly against the pull of the weight, moving the catch it out of the path to be followed by the stud it when the treadle is depressed.

At the same time the lower end 56 of the rod i8 strikes the abutment 58 on the lever or dog 62 and depresses it also until further movement of both the rod i6 and the dog 62 is prevented by the stop 6 3. The operator is then free to depress the treadle 34!.

For the reasons already pointed out, it is desirable to make it necessary for the operator to move the handle l0 each time that he wishes to restart the machine after having stopped it. This is accomplished by locating the rod l8 surficiently near the stud All on the arm 38 of the treadle 3|] so that as the treadle is depressed the stud 4B approaches the rod i8 and strikes it, moving it laterally away from the lever 48. This disengages the shoulder 54 from the plate 28 on the lever, which latter member is then returned to its normal position by the action of the weight. As the stud progresses downwardly and moves the rod further laterally, the end 56 of the rod is forced over the abutment 58 on the lever 62, thereby disengaging the abutment 58 from the end of the rod 58. This permits the dog 62 to be returned to its normal position by the action of the weight.

When the treadle 38 is released, thereby stopping the machine, the stud 4i] strikes against the end of the catch 46. The surface of the end of the catch 45 is at an angle to the path of the stud 4! Consequently, as the stud progresses upwardly, striking against this angular surface, it forces the catch downwardly, thus permitting the stud to pass by it. As the treadle reaches its initial position, the lever 18 returns to its normal position against the stop 50, the catch thus locking the treadle in that position.

The treadle cannot then be again depressed until the handle H! has been permitted to return to its normal position, thus raising the rod 18 so that its end 56 is lifted above the abutment 58. The action of the spring 20 then moves the rod I8 laterally so that the shoulder 54 again engages the plate 52. tempt to fasten the handle in releasing position and thus avoid the necessity of operating the handle before starting the machine each time, the end of the rod 56 striking against the side of the abutment 58 would hold the shoulder 5d out of cooperative relation with the plate 52.

It will be noticed that there is a short space between the stud MI and the catch 46. This, in practice, is sufficient to permit the treadle to be slightly depressed so that if a fly wheel and brake are incorporated in the machine, the brake may be released, thus permitting rotation of the fly wheel by hand to facilitate the changing and adjustment of the work engaging parts of the machine.

If the operator should at- Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A safety device for presses and the like comprising a starting treadle, means for locking said treadle in inoperative position, manually operated means for releasing said locking means, and means for holding said releasing means out of cooperative relation to the locking means, from the time the releasing means is operated, until the latter is returned to its initial position.

2. A safety device for presses and the like comprising a starting treadle, a catch constructed and arranged to hold said treadle in inoperative position, means for releasing said catch, a manually operated rod arranged to engage said means, and a dog constructed and arranged to hold said rod out of engagement with said releasing means until the rod is returned to its starting position.

3. A safety device for presses and the like comprising a starting treadle, means for locking said treadle in inoperative position, means for releasing said locking means, a manually operated rod having a shoulder arranged to engage said releasing means, and a dog constructed and arranged to hold said shoulder out of engagement with said releasing means from the time the releasing means is operated until it is returned to its initial position.

4. A safety device for presses and the like comprising a starting treadle, a stud on said treadle, means arranged to engage said stud and to lock said treadle in inoperative position, manually operated means for releasing said stud-engaging means, and means actuated by depression of the treadle to hold said releasing means out of cooperative relation to the locking means until said releasing means is returned to its initial position.

5. A safety device for presses and the like comprising a starting treadle, a catch constructed and arranged to lock said treadle in inoperative position, a manually operated shouldered rod for releasing said catch, and a dog arranged to hold said rod out of operative connection with said catch from the time said rod is depressed until it is returned to its initial position.

WILFRID THOMAS MINETT. 

